1. Field of the Invention
The present invention relates to a method for linking segments and a linking tool, and more particularly to a method for linking segments that are used as an assembly unit of a pipe for rehabilitating existing pipes or pipelines, and to a linking tool used in this method.
2. Description of the Related Art
In cases where sewage pipes or other pipelines that are buried underground have aged, methods for constructing a pipe lining have already been proposed and are being employed in practical applications.
With the aforementioned methods for constructing a pipe lining, a pipe-lining material, which is formed, e.g., by impregnating a tubular resin-adsorbent material with an uncured thermosetting resin, is inserted into a pipeline via fluid pressure while being everted, and the impregnated thermosetting resin is cured by heating the pipe-lining material in the state where the pipe-lining material is pressed against the inner circumferential wall of the pipeline by fluid pressure. This allows a plastic pipe to be installed within the pipeline to be repaired.
In another well-known method for repairing a pipeline using a rehabilitating pipe (Japanese Laid-open Patent Application Nos. 2003-286742 and 2005-299711), a segment made of a plastic material is used which is integrally composed of an internal surface plate that constitutes the inner circumferential surface of the rehabilitating pipe and an outer-wall plate that is vertically disposed on the peripheral edges of the internal surface plate. Segments are linked in the circumferential direction to assemble pipe units, which are then linked in the longitudinal direction of the pipe via a linking member to assemble the rehabilitating pipe. This method is used for large-bore pipelines.
When linked together in the longitudinal direction of the pipe as disclosed in Japanese Laid-open Patent Application Nos. 2003-286742 and 2005-299711, the segments are linked using a linking tool provided with a screw. A screw-fastening tool is therefore necessary, and time is required to tighten the screw. The screw may not be able to be turned when the operation is performed in confined spaces; moreover, the operation is troublesome and repetitive even when the screw can be turned. A significant burden is therefore placed on the worker, resulting in lengthened operational time.